source: [浴衣の少女が両手を振りながら謙遜しているGIF画像｜無料GIF画像検索 GIFMAGAZINE 449177]

SHY, BASHFUL, DIFFIDENT, MODEST, COY mean not inclined to be forward.

SHY implies a timid reserve and a shrinking from familiarity or contact with others.

e.g. shy with strangers

BASHFUL implies a frightened or hesitant shyness characteristic of childhood and adolescence.

e.g. a bashful boy out on his first date

DIFFIDENT stresses a distrust of one's own ability or opinion that causes hesitation in acting or speaking.

e.g. felt diffident about raising an objection

MODEST suggests absence of undue confidence or conceit.

e.g. modest about her success

COY implies a pretended shyness.

e.g. put off by her coy manner

CHASTE, PURE, MODEST, DECENT mean free from all taint of what is lewd or salacious.

CHASTE primarily implies a refraining from acts or even thoughts or desires that are not virginal or not sanctioned by marriage vows.

e.g. they maintained chaste relations

PURE differs from CHASTE in implying innocence and absence of temptation rather than control of one's impulses and actions.

e.g. the pure of heart

MODEST and DECENT apply especially to deportment and dress as outward signs of inward chastity or purity.

e.g. preferred more modest swimsuits

e.g. decent people didn't go to such movies

1. unassuming or moderate in the estimation of one's abilities or achievements:

｟ほめて｠ «…について/…の点で» 謙虚な, 控えめな, 遠慮がちな «about/in» (↔ immodest; → humble)

e.g. he was a very modest man, refusing to take any credit for the enterprise.

2. (of an amount, rate, or level) relatively moderate, limited, or small:

〈数･量･規模･価値などが〉(期待よりも)大きくない, 高くない; 多く［大きく］ない(が適度な), そこそこの〈収入･成功など〉; 控えめな; 質素な

e.g. drink modest amounts of alcohol

e.g. employment growth was relatively modest.

(of a place in which one lives, eats, or stays) not excessively large, elaborate, or expensive:

e.g. we had bought a modest house.

3. (of a woman) dressing or behaving so as to avoid impropriety or indecency, especially to avoid attracting sexual attention:

｟やや古｠ 〈(女性の)服装･態度などが〉肌の露出を抑えた; 派手でない, 地味な; つつましい

e.g. the modest women wear long-sleeved dresses and all but cover their faces.

(of clothing) not revealing or emphasizing the figure:

e.g. modest dress means that hemlines must be below the knee.

mid 16th century: from French modeste, from Latin modestus ‘keeping due measure’, related to modus ‘measure’.